Arrest warrants are expected to be issued soon for seven current students and alumnus of Samut Prakan Technological College over the fatal shooting on Monday (July 22) of a Bangkok College of Industrial Technology student in Bangkok's Bang Na district, Metropolitan Police Division 5 chief Pol Maj-General Mongkol Warunno said on Wednesday morning.

The seven suspects face four charges: conspiring to murder, attempted murder (as one student was also wounded in this attack), illegal possession of firearms, and illegal possession of explosives (ping-pong bombs).

Police said 22 people were involved in the fatal attack on Chanathip Piamyoo and his five friends near the Wat Sri Eium area. They used 12 motorcycles, three of which had already been seized by police, Mongkol told reporters outside Bang Na Police Station where he had gone to follow up on progress in the case investigation.

He said police had interviewed many witnesses after the attack, including six youths who yielded useful information about the events and those who had used guns and ping-pong bombs, enabling police to seek arrest warrants, he said.

To prevent any violent fallout from the event, Mongkol said police had invited executives and teachers of the two educational institutions for discussions later on Wednesday to implement preventive measures.